Computer considerations for real time simulation of a generalized rotor model

Scaled equations were developed to meet requirements for real time computer simulation of the rotor system research aircraft. These equations form the basis for consideration of both digital and hybrid mechanization for real time simulation. For all digital simulation estimates of the required speed in terms of equivalent operations per second are developed based on the complexity of the equations and the required intergration frame rates. For both conventional hybrid simulation and hybrid simulation using time-shared analog elements the amount of required equipment is estimated along with a consideration of the dynamic errors. Conventional hybrid mechanization using analog simulation of those rotor equations which involve rotor-spin frequencies (this consititutes the bulk of the equations) requires too much analog equipment. Hybrid simulation using time-sharing techniques for the analog elements appears possible with a reasonable amount of analog equipment. All-digital simulation with affordable general-purpose computers is not possible because of speed limitations, but specially configured digital computers do have the required speed and consitute the recommended approach

Virtual Proximity to Promote Expatriate Cultural Adjustment, Innovation, and the Reduction of Stress Levels

Given the dramatic increase in the number of expatriates living and working abroad, there is a need to advance the research into how to make sure these employees achieve success on their assignments. Often, these expatriates assume managerial roles and are intended to be the gatekeepers of information. Typically, this information is necessary for the success of their colleagues, in both their home country and their host country. The expatriate’s role is to facilitate the integration of organizational knowledge from both their home and host countries, as well as key sources in their host country’s local environment. However, historically, there has been an exceptionally high failure rate in expatriate engagements. There are various factors discussed in the literature related to this failure rate including the stress of cultural integration and isolation from family. This often interferes with the expatriate being able to perform of their key responsibilities, which is to innovate. This research will launch pilot studies to investigate the use of social media, and computer mediated communications, to develop virtual proximity, its effects on cultural integration, the maintenance of professional relationships on a global scale, and its effect on the reduction of stress and the innovation process

Molecular dynamics study of structure and reactions at the hydroxylated Mg(0001)/bulk water interface

A molecular level understanding of the aqueous Mg corrosion mechanism will be essential in developing improved alloys for battery electrodes, automobile parts, and biomedical implants. The structure and reactivity of the hydroxylated surface is expected to be key to the overall mechanism because (i) it is predicted to be the metastable surface state (rather than the bare surface) under a range of conditions and (ii) it provides a reasonable model for the outer corrosion film/water interface. We investigate the structure, interactions, and reactivity at the hydroxylated Mg(0001)/water interface using a combination of static Density Functional Theory calculations and second-generation Car–Parrinello ab initio molecular dynamics. We carry out detailed structural analyses into, among other properties, near-surface water orientations, favored adsorption sites, and near-surface hydrogen bonding behavior. Despite the short timescale (tens of ps) of our molecular dynamics run, we observe a cathodic water splitting event; the rapid timescale for this reaction is explained in terms of near-surface water structuring lowering the reaction barrier. Furthermore, we observe oxidation of an Mg surface atom to effectively generate a univalent Mg species (Mg+). Results are discussed in the context of understanding the Mg corrosion mechanism: For example, our results provide an explanation for the catalytic nature of the Mg corrosion film toward water splitting and a feasible mechanism for the generation of the univalent Mg species often proposed as a key intermediate

Implicit and explicit host effects on excitons in pentacene derivatives

An ab initio study of the effects of implicit and explicit hosts on the excited state properties of pentacene and its nitrogen-based derivatives has been performed using ground state density func- tional theory (DFT), time-dependent DFT and ∆SCF. We observe a significant solvatochromic redshift in the excitation energy of the lowest singlet state (S 1 ) of pentacene from inclusion in a p -terphenyl host compared to vacuum; for an explicit host consisting of six nearest neighbour p -terphenyls, we obtain a redshift of 65 meV while a conductor-like polarisable continuum model (CPCM) yields a 78 meV redshift. Comparison is made between the excitonic properties of pen- tacene and four of its nitrogen-based analogues, 1,8-, 2,9-, 5,12-, and 6,13-diazapentacene with the latter found to be the most distinct due to local distortions in the ground state electronic struc- ture. We observe that a CPCM is insufficient to fully understand the impact of the host due to the presence of a mild charge-transfer (CT) coupling between the chromophore and neighbouring p -terphenyls, a phenomenon which can only be captured using an explicit model. The strength of this CT interaction increases as the nitrogens are brought closer to the central acene ring of pentacene

Skin in the Game? Experimental Reactions to Prospective Reputational Damage by Corporate Personnel

All organizations confront the possibility of scandal; however, the reputational threat caused by scandal is exacerbated when these events are not properly addressed. Since scandals also have the potential to adversely affect organizational personnel, dilemmas arise regarding traditional ideas of employee agency. In this study, we conduct an experiment manipulating the severity of the reputational threat and its financial consequences for decision-makers, using actual corporate officers and internal auditors. One key question is this: “Are corporate decision-makers’ responses to potential scandals affected by whether they, as incentivized individuals (via stock options), have “skin in the game?” Findings indicate that corporate personnel believe corporations should respond aggressively to scandals having potential reputational consequences; however, they prefer not to proactively respond to reputational threats when expected personal gains are likely to be jeopardized. Internal auditors, by contrast, are less sensitive to personal gains. An archival supplementary analysis supports these findings by suggesting that equity compensation was 17.7% higher before a severe reputational event

An eccentrically perturbed Tonks-Girardeau gas

We investigate the static and dynamic properties of a Tonks-Girardeau gas in a harmonic trap with an eccentric $\delta$-perturbation of variable strength. For this we first find the analytic eigensolution of the single particle problem and use this solution to calculate the spatial density and energy profiles of the many particle gas as a function of the strength and position of the perturbation. We find that the crystal nature of the Tonks state is reflected in both the lowest occupation number and momentum distribution of the gas. As a novel application of our model, we study the time evolution of the the spatial density after a sudden removal of the perturbation. The dynamics exhibits collapses and revivals of the original density distribution which occur in units of the trap frequency. This is reminiscent of the Talbot effect from classical optics.Comment: Comments and suggestions are welcom